T-cell acute lymphoblastic leukemia (T-ALL) is a devastating form of cancer characterized by malignant, immature white blood cells that continuously multiply and are overproduced in the bone marrow. T-ALL leads to pain and damage throughout the body and eventually death due to the crowding out of normal cells in the bone marrow and the spreading of tumor cells to other organs. 50% of T-ALL cases harbor a mutation in the Notch signaling pathway. As a result, gamma secretase inhibitors (GSI) that inhibit cleavage of the activated form of Notch have been developed. Unfortunately, early relapse and refractory disease are common in T-ALL cases due to the transient response of the cancer to a GSI. Additionally, GSI treatment is also associated with toxicity, especially damage to the gastrointestinal tract.